Introduction
Nowadays, industrial activity in the world has grown very fast. In addition to induces positive impacts, the growth of industry also generates a new problem for the environment and so we need to search an effective and efficient handling ways of negative impacts such as waste. One example of pollutions due to industrial wastes is a pollution caused by waste containing in dissolved heavy metals. Waste with a high content of heavy metals could be dangerous pollutants. One of heavy metals that are harmful is chromium. Chromium contained in waste usually has a valence of three (Cr3+) and valence of six (Cr6+). Heavy metals such as chromium waste derived from metal plating industry (electroplating), paints/pigments industry and leather tanning industries. Cr waste (VI) is concerned because of its carcinogenic properties. Interestingly, only Cr(VI) which are carcinogenic, while Cr (III) is not (Mariana, et al, 2006). The toxicity level of Cr (III) is only about 1/100 times that of Cr (VI). Some of handling methods of Cr (VI) waste has been conducted through chemical reduction and ion exchange (Slamet et al. 2003).
In general, the methods used for handling of Cr (VI) waste require high cost and long process. There are other alternatives for removal of chromium from industrial waste by adsorption method using biomaterials. This method is a very promising method for treating industrial waste, mainly because it is cheap and has a high absorption capacity. Some examples of research that has been done by using biomaterials as bio-sorbent to absorb Cr (III) by using seaweed (Sudiarta, 2009), the utilization of peanut shell as a bio-sorbent for reactive dye of Cibacron Red (Aprilia S, 2009), absorption of copper ions using chitosa...
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Figure 3 shows the relationship of temperature to absorption capacity of Cr (VI). At temperatures of 35 ºC and 50 ºC, the contact time of 120 minutes and concentration of 50 mg/L, absorption capacity was obtained as much as 1.5256 and 1.6752 mg/g, respectively. Based on these data it can be seen that the higher of applied temperature then the greater of absorption capacity. This is probably due to the empty pores exist in the adsorbent will get bigger. Therefore if it is used to absorb the adsorbate at the same temperature then absorption capacity become greater.
Conclusions
The optimum absorption process of Cr6+ metal with adsorbent dose of 1 g and contact time of 60 minutes was obtained at concentration of 50 mg/L and temperature of 50º C. The best absorption process of Cr (VI) metal ions using guava leaves was obtained on contact time for 30 minutes.
The mean for the temperatures is 0.116 and the solvents is 20. We predicted the 37 Celsius would be the most absorbed, but it was the -20 Celsius which can be seen in the graph above.
Introduction: The purpose of this lab was to cycle solid copper through a series of chemical forms and return it to its original form. A specific quantity of copper undergoes many types of reactions and goes through its whole cycle, then returns to its solid copper to be weighted. We observed 5 chemical reactions involving copper which are: Redox reaction (which includes all chemical reactions in which atoms have their oxidation state changed), double displacement reaction, precipitation reaction, decomposition reaction, and single displacement reaction. 4HNO3(aq) + Cu(s) --> Cu (NO3)2(aq) + 2H2O (l) + 2NO2(g) Oxidation reduction reaction Cu (NO3)2(aq) + 2 NaOH (aq) --> Cu (OH)2(s) + 2 NaNO3(aq) Precipitation Reaction Cu (OH)2(s) + heat --> CuO (s) + H2O (l) Decomposition reaction CuO (s) + H2SO Data Results: (mass of copper recovered / initial mass of copper) x 100 Mass of copper recovered: 0.21 Initial mass of copper: 0.52 (0.21/0.52)x100 =40.38%.
Using the spectrophotometer, the absorption of each sample was measured by scanning the wavelengths. After calibrating the spectrophotometer with the blank test tube, each sample was placed into the spectrophotometer and read at 360nm. Observations were continued for each pigment sample increasing the wavelength by 20nm increments. Once these absorbance values were recorded, absorption spectra for each pigment were graphed.
In the first part of this project, two cation elimination tests and one cation confirmation test were performed. 10 drops of 4 cation solutions: potassium, zinc(II), copper(II)
The molar absorption coefficient can be found in an absorption spectrum. The absorption spectra is generate...
Waste In The Bay, What Else Can I Say? Lay a hand for Jamaica Bay! Jamaica Bay, also known as Dead Horse Bay, has a toxic past filled with pollution and decaying carcasses (Roberts,2010). For over a decade, Jamaica Bay has been the main dumping site for waste treatment plants, oozing contaminants from a nearby landfill, runoff from the Belt Parkway and airplane fuel (Roberts,2010). To address this issue of pollution, finding the source of the contaminate would help reduce the continuous depletion of Jamaica Bay.
The same procedure was done using 10ml of CV and 20ml of sodium hydroxide, both separately diluted to 50ml and added in a large beaker. The absorbance was recorded. In the last trial, 10ml of CV, 10ml of NaOH were diluted to 50ml. Before adding the two mixtures, 1ml of soap was added to the NaOH solution and then poured into a large beaker, along with the CV. Absorbance was recorded and the materials
Neidig, H. A., and J. N. Spencer. "Precipitating Lead Chromate on a Small Scale." General Chemistry For Engineering And Science. Mason: Cengage Learning, 2012. 83-90. Print. Signature Lab Ser.
In this experiment, [Co(NH3)5ONO]Cl¬2 was synthesized with a yield of 1.4314 g. It was then used to obtain UV-Vis Spectroscopy data with other prepared cobalt complexes including [Co(NH3)5(H2O)]Cl3, [Co(NH3)5(Cl)]Cl2 , Co(NH3)5(NO2)]Cl2 and [Co(NH3)6]Cl3. Each compound was a different color. Color, by definition, represents the wavelengths of UV light that a particle reflects. UV-Vis spectroscopy measures the amount of UV light absorbed. The easy way to determine wavelength of absorption from the color of the solution was the use of a color wheel like in Figure 1. The wavelengths of the color opposite of the solution’s color in the color wheel were the expected wavelengths of absorption. Co(NH3)5ONO]Cl¬2 was an reddish-orange color so its wavelength
I have chosen the topic of food waste and the impact on the environment. I will discuss the ridiculous amount of food that is wasted each year and the staggering amount of waste that could be avoided just by planning ahead, and purchasing from farmer’s markets and avoiding the main stream supermarkets who set such high standards on the aesthetic of produce that tonnes are wasted for no reason other then shape.
The diffusion rates of potassium permanganate, KMnO4 (MW: 158 g/mole), potassium dichromate, K2Cr2O7 (MW: 294 g/mole), and methylene blue (MW: 379 g/mole) were compared and observed on an agar-water gel. An amount of each of the three substances was dropped on the wells of the gel. The diffusion rates were recorded by measuring the diameters of the substances at a regular three-minute interval for thirty minutes. Potassium permanganate had the biggest diameter after 30 minutes. Methylene blue had the smallest diameter. Thus, the molar weight of a substance highly affects its diffusion rate.
Pharmaceutical waste seems to be one of the dominant elements that are prevalent in our waters, and other aspects of the environment. These aforementioned elements are largely becoming a concern in today’s society because its effects have proven to be harmful towards our environment, and all of its existing forms of life. Through various ways, whether controllable or uncontrollable, pharmaceutical waste slowly and increasingly multiplies its presence within the environment. Additionally, it eventually trickles down into our waterways and causes a large array of damages. Some of the most common ways that this waste gets into the water includes: disposal through the drainage systems, farming fertilization methods and the maintenance of treatment plants. These methods are self-explanatory through their brief discussions, but it helps decipher whether the disposal of these dangerous wastes are intentional or not.
As humanity develops new technology, the magnitude and severity of waste increases. When computers were developed, it widely was believed that the need for paper would be eliminated. On the contrary this was widely proven false and we are now utilizing more paper than ever. Canada is not an exception as the typical Canadian generates an average of three pounds of solid waste each day1. This alone shows what a careless species we have become- using and disposing materials without even considering the damage we are causing. With half a trillion tones of waste around the world, only 25% may be reused for a second or third time and less than 5% can be renewed limitlessly1. These facts are true only in developed countries. Since these traditional waste reduction methods have been proven inefficient, we must endorse new innovative technology to arrive at a solution.
...e industries, textile industries are considered as one of the major sources of wastewater in ASEAN countries. Dyes are also used in industries such as rubber, paper & pulp, dye & dye intermediate industries, pharmaceutical, tannery, food technology, hair coloring, plastic, cosmetic etc. There are more than 10,000 commercially available dyes with over 7x105 tones of dyestuff being produced annually across the world2.. The textile industry consumes more than 107 kg of dye per year of which 90% ending up on fabrics3. Of this total usage 10- 15% of the dye is lost during the dyeing process and released with the effluent. Colour is contributed by phenolic compounds such as tannins, lignins (2-3%) and organic colourants (3-4%) and with a maximum contributions from dye and dye intermediates which could be sulphur/ mordant/ reactive/ cationic/ dispersed/acid/azo vat dye4.
Wastes are the products of our consumptions in our daily life routines such as lunch, work, school and other things we do. Little things such as throwing out a piece of paper, we are producing waste by the seconds. After we consume a product we usually throw out what’s left that can’t be consumed any further. Results in producing waste, substance that are born after it’s been use or consume by us. At the end of each day we throw out a bag full of garbage, all of the materials in that bag (paper towels, cans, leftover foods and many other material’s) all of these are waste. Hospitals produce medical waste such as use needles for treating patients. Corporations produce papers, plastics, tires, steels, cans and many other type of solid waste which contribute to the pollutions that cause health risk and other environmental issues.